/* F01EF_T1W_F C++ Header Example Program.
*
* Copyright 2019 Numerical Algorithms Group.
* Mark 27, 2019.
*/
#include <dco.hpp>
#include <nag.h>
#include <nagx04.h>
#include <nagad.h>
#include <stdio.h>
#include <string>
#include <iostream>
using namespace std;
extern "C"
{
static void (NAG_CALL f)(void* &ad_handle,
Integer &iflag,
const Integer &n,
const nagad_t1w_w_rtype x[],
nagad_t1w_w_rtype fx[],
Integer iuser[],
nagad_t1w_w_rtype ruser[]);
}
int main(void)
{
int exit_status = 0;
void *ad_handle = 0;
Integer ifail = 0;
NagError fail;
INIT_FAIL(fail);
cout << "F01EF_T1W_F C++ Header Example Program Results\n\n";
// Skip heading in data file
string mystr;
getline (cin, mystr);
// Read problem size and number of right-hand-sides
Integer n;
cin >> n;
// Allocate arrays containing A and its factorized form, B
// and the solution X.
nagad_t1w_w_rtype *a=0, *a_in=0;
double *ar=0;
a = new nagad_t1w_w_rtype [n*n];
a_in = new nagad_t1w_w_rtype [n*n];
ar = new double [n*n];
// Read the matrix A, register and copy
double dd;
for (int i = 0; i<n; ++i) {
for (int j = i; j<n; ++j) {
cin >> dd;
Integer k = i + j*n;
a_in[k] = dd;
}
}
// Create AD configuration data object
ifail = 0;
x10aa_t1w_f_(ad_handle,ifail);
// Find exp(A)
Integer iflag, iuser[1];
nagad_t1w_w_rtype ruser[1];
for (int i = 0; i<n; i++) {
{
double inc = 1.0;
Integer k = i*n+i;
nagad_t1w_inc_derivative(&a_in[k],inc);
}
for (int j = 0; j<n; ++j) {
for (int l = j; l<n; ++l) {
Integer k = j + l*n;
a[k] = a_in[k];
}
}
ifail = 0;
f01ef_t1w_f_(ad_handle,"U",n,a,n,f,iuser,ruser,iflag,ifail,1);
if (i==0) {
// Print exp(A)
for (int j = 0; j<n; j++) {
for (int l = j; l<n; l++) {
int k = j + l*n;
ar[k] = nagad_t1w_get_value(a[k]);
}
}
cout << endl;
x04cac(Nag_ColMajor,Nag_UpperMatrix,Nag_NonUnitDiag,n,n,ar,n,
" Exp(A)",0,&fail);
}
for (int j=0; j<n; j++) {
Integer l = j + j*n, p = j + i*n;
double dd = nagad_t1w_get_derivative(a[l]);
ar[p] = dd;
}
{
double zero = 0.0;
Integer k = i*n+i;
nagad_t1w_set_derivative(&a_in[k],zero);
}
}
cout << "\n\n Derivatives calculated: First order tangents\n";
cout << " Computational mode : algorithmic\n";
cout << "\n Derivatives of diagonal of f(A) w.r.t diagonal of A:\n";
// Print derivatives
cout << endl;
x04cac(Nag_ColMajor,Nag_GeneralMatrix,Nag_NonUnitDiag,n,n,ar,n,
" d(fA(i,i)/dA(j,j)",0,&fail);
// Remove computational data object
ifail = 0;
x10ab_t1w_f_(ad_handle,ifail);
delete [] a;
delete [] a_in;
delete [] ar;
return exit_status;
}
static void (NAG_CALL f)(void* &ad_handle,
Integer &iflag,
const Integer &n,
const nagad_t1w_w_rtype x[],
nagad_t1w_w_rtype fx[],
Integer iuser[],
nagad_t1w_w_rtype ruser[])
{
for (int i=0; i<n; ++i) {
fx[i] = cos(x[i]);
}
}